In the highly informational era, many electronic devices are connected with the information systems. It is an important issue how to accurately handle the states or the related information of users and well arrange the information and the interactive services required by the users. Among all of the user-related contexts, location is one of the most important information, because many practical applications deeply rely on the locations of users. It is a great challenge how to obtain more precise and reliable location information.
In the conventional user localization and tracking apparatus, the major stream is using cameras and mobile equipments, such as RFIDs, infrared, ultrasonic, cell phone or wireless transmission devices, to obtain the location information of a user. The system can estimate the approximate location of the user in a specific environment through cameras. However, the configuration of cameras needs lots of complicated calibration in advance. If a user does not have the background or training, it is easy to make the cameras fail to do their best, or even causes erroneous estimates or failure. Furthermore, cameras can capture more details of the activities, which leads to privacy violation.
On the other hand, if the localization and tracking function is performed by mobile devices, it does not need much calibration, but it causes inconvenience for the users since they have to carry the devices. If a user forgets to carry the mobile equipment, the tracking function will be completely unavailable. Moreover, if the wireless signal, such as the signal strength or the transmission time, is directly used to locate and track the user, the deployment cost is cheaper than others. However, the signal may be easily affected by the variations of the environment; for example, the moving subjects or the layout may affect the stability and the accuracy of the wireless signal transmission. Furthermore, the battery-powered devices are gradually depleted over time, which in turn deteriorates the stability of the tracking system.
The advantages of using the wireless pressure sensing module to localize and track users can overcome the drawbacks mentioned above, such as the complicated pre-calibration, the privacy violation and inconvenience due to carrying the devices. Nowadays, regarding the current studies of the pressure sensing floor, the prior work uses wired load cells with fixed deployment layouts, whose disadvantage is the cost to re-layout and maintain the system after the floor is settled. We found the wireless pressure sensing pad used to detect the presence of people, but there is no relevant off-the-shelf products we can purchase directly at the moment of proposing the wireless pressure sensing module. To sum up, there is no floor device using wireless sensing networks to provide multi-resolution of tracking granularity so as to provide the natural, precise and convenient location-aware services.
In order to overcome the drawbacks in the related prior works, a pressure sensing based localization and tracking system is provided. The particular design in the present invention not only solves the problems described above, but also is easy to be implemented. Thus, the invention has its industry utility.